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101.
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多数重要的功能基因属于多基因家族,这些家族成员间存在功能冗余,高效的多基因干扰体系对研究多基因家族成员的生物学功能及其分子调控机制具有重要意义。对pCAMBIA1301载体改造,构建了适用于植物的多基因干扰体系pCAMBIA1301m和pCAMBIA1301s。使用该多基因干扰体系构建了四基因的干扰载体pCAMBIA1301m:35S∷SlPP2C1-2-3-4,4个目标基因为来源于番茄PP2C家族A组的PP2C1、PP2C2、PP2C3和PP2C4,并通过遗传转化导入番茄,用GUS染色和PCR检测转基因阳性植株,再利用RT-qPCR技术检测T1和T2代转基因植株中目标基因的干扰效率,用T2代种子分析转基因番茄对ABA敏感性。结果表明,应用该干扰体系成功获得了四基因干扰的转基因植株35S∷SlPP2C1-2-3-4。在转基因番茄中4个目标基因的表达量显著低于野生型,其干扰效率均高于70%,转基因番茄种子萌发具有强烈的ABA不敏感性。多基因干扰体系能高效地同时沉默多个目标基因。 相似文献
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Yunqiang Zhang Jianyu Liu Lu Guan Dongxue Fan Feiruo Xia Andong Wang Ying Bao Yongnan Xu 《化学与生物多样性》2023,20(3):e202200940
Zea mays (Z. mays) is one of the main cereal crops in the world, and it′s by-products have exhibited medicinal properties to explore. This article intends to review the chemical compositions and pharmacological activities of by-products of Z. mays (corn silks, roots, bract, stems, bran, and leaves) which support the therapeutic potential in the treatment of different diseases, with emphasis on the natural occurring compounds and detailed pharmacological developments. Based on this review, 231 natural compounds are presented. Among them, flavonoids, terpenes, phenylpropanoids, and alkaloids are the most frequently reported. The by-products of Z. mays possess diuretic effects, hepatoprotective, anti-diabetic, antioxidant, neuroprotective, anti-inflammatory, anti-cancer, plant protection activity, and other activities. This article reviewed the phytochemistry and pharmacological activities of Z. mays for comprehensive quality control and the safety and effectiveness to enhance future application. 相似文献
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Bao Yang Jianwu Li Jiayu Yan Ke Zhang Zhewen Ouyang Yefei Lu Huili Wei Qing Li Xuan Yao Shaoping Lu Yueyun Hong Xuemin Wang Liang Guo 《植物学报(英文版)》2023,65(11):2421-2436
Phosphorus is a major nutrient vital for plant growth and development, with a substantial amount of cellular phosphorus being used for the biosynthesis of membrane phospholipids. Here, we report that NON-SPECIFIC PHOSPHOLIPASE C4 (NPC4) in rapeseed (Brassica napus) releases phosphate from phospholipids to promote growth and seed yield, as plants with altered NPC4 levels showed significant changes in seed production under different phosphate conditions. Clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated nuclease 9 (Cas9)-mediated knockout of BnaNPC4 led to elevated accumulation of phospholipids and decreased growth, whereas overexpression (OE) of BnaNPC4 resulted in lower phospholipid contents and increased plant growth and seed production. We demonstrate that BnaNPC4 hydrolyzes phosphosphingolipids and phosphoglycerolipids in vitro, and plants with altered BnaNPC4 function displayed changes in their sphingolipid and glycerolipid contents in roots, with a greater change in glycerolipids than sphingolipids in leaves, particularly under phosphate deficiency conditions. In addition, BnaNPC4-OE plants led to the upregulation of genes involved in lipid metabolism, phosphate release, and phosphate transport and an increase in free inorganic phosphate in leaves. These results indicate that BnaNPC4 hydrolyzes phosphosphingolipids and phosphoglycerolipids in rapeseed to enhance phosphate release from membrane phospholipids and promote growth and seed production. 相似文献
107.
Xinyue Ye Jian Wang Pengfei Xu Xiaoqian Yang Qixue Shi Genyan Liu Zhaoshi Bai Changlin Zhou Lingman Ma 《Microbial biotechnology》2023,16(9):1755-1773
Polymyxin resistance is conferred by MCR-1 (mobile colistin resistance 1)-induced lipopolysaccharide (LPS) modification of G− bacteria. However, the peptide MSI-1 exerts potent antimicrobial activity against mcr-1-carrying bacteria. To further investigate the potential role of MCR-1 in improving bacterial virulence and facilitating immune evasion, and the immunomodulatory effect of peptide MSI-1, we first explored outer membrane vesicle (OMV) alterations of mcr-1-carrying bacteria in the presence and absence of sub-MIC MSI-1, and host immune activation during bacterial infection and OMV stimulation. Our results demonstrated that LPS remodelling induced by MCR-1 negatively affected OMV formation and protein cargo by E. coli. In addition, MCR-1 diminished LPS-stimulated pyroptosis but facilitated mitochondrial dysfunction, further aggravating apoptosis in macrophages induced by OMVs of E. coli. Similarly, TLR4-mediated NF-κB activation was markedly alleviated once LPS was modified by MCR-1. However, peptide MSI-1 at the sub-MIC level inhibited the expression of MCR-1, further partly rescuing OMV alteration and attenuation of immune responses in the presence of MCR-1 during both infection and OMV stimulation, which can be exploited for anti-infective therapy. 相似文献
108.
Jing‐Fang Guo Baosheng Wang Zhan‐Lin Liu Jian‐Feng Mao Xiao‐Ru Wang Wei Zhao 《植物分类学报:英文版》2023,61(1):143-156
Endemic species are important components of regional biodiversity and hold the key to understanding local adaptation and evolutionary processes that shape species distributions. This study investigated the biogeographic history of a relict conifer Pinus bungeana Zucc. ex Endl. confined to central China. We examined genetic diversity in P. bungeana using genotyping-by-sequencing and chloroplast and mitochondrial DNA markers. We performed spatial and temporal inference of recent genetic and demographic changes, and dissected the impacts of geography and environmental gradients on population differentiation. We then projected P. bungeana's risk of decline under future climates. We found extremely low nucleotide diversity (average π 0.0014), and strong population structure (global FST 0.234) even at regional scales, reflecting long-term isolation in small populations. The species experienced severe bottlenecks in the early Pliocene and continued to decline in the Pleistocene in the western distribution, whereas the east expanded recently. Local adaptation played a small (8%) but significant role in population diversity. Low genetic diversity in fragmented populations makes the species highly vulnerable to climate change, particularly in marginal and relict populations. We suggest that conservation efforts should focus on enhancing gene pool and population growth through assisted migration within each genetic cluster to reduce the risk of further genetic drift and extinction. 相似文献
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Frankia菌种保藏 总被引:5,自引:0,他引:5
对用4种方法保藏的Frankia菌,进行了培养物存活、形态及其固氮活性的检测.发现在无氮液体培养基中保藏6年的Frankia.菌丝断裂,孢囊不完整.同期经有氮液体保藏的Frankia菌孢囊较完整.冷冻干燥保藏3.5年和砂管保藏8年,孢囊和菌丝均较完整.上述方法保藏的菌种,经活化后均能生长,且具有典型的Frankia菌形态特征和固氮活性.4种方法比较,无氮液体保藏法的菌体细胞生长速度快,固氮活性强,有侵染结瘤能力. 相似文献